public BigNum ShiftDigitsToHigh(BigNum a, int i)
{
BigNum result = new BigNum(a.array.Length + i);
for (int k = 0; k < a.array.Length; k++)
{
result.array[k + i] = a.array[k];
}
return(result);
}
public static int HighNotZeroIndex(BigNum a)
{
for (var i = a.array.Length - 1; i >= 0; i--)
{
if (a.array[i] > 0)
{
return(i);
}
}
return(0);
}
public static BigNum LongMulOneDigit(BigNum a, ulong b)
{
BigNum c = new BigNum(a.array.Length + 1);
for (int i = 0; i < a.array.Length; i++)
{
temp = a.array[i] * b + carry;
c.array[i] = temp & 0xffffffff;
carry = temp >> 32;
}
c.array[a.array.Length] = carry;
return(c);
}
public int Bitlen(BigNum a)
{
var bits = 0;
var index = HighNotZeroIndex(a);
var temp = a.array[index];
while (temp > 0)
{
temp >>= 1;
bits++;
}
return(bits + 32 * index);
}
public static BigNum RemoveHighZeros(BigNum c)
{
int i = c.array.Length - 1;
while (c.array[i] == 0)
{
i--;
}
BigNum result = new BigNum(i + 1);
Array.Copy(c.array, result.array, i + 1);
return(result);
}
public int Compare(BigNum a, BigNum b)
{
var maxlen = Math.Max(a.array.Length, b.array.Length);
Control(a, b, maxlen);
for (int i = a.array.Length - 1; i > -1; i--)
{
if (a.array[i] > b.array[i])
{
return(1);
}
if (a.array[i] < b.array[i])
{
return(-1);
}
}
return(0);
}
public BigNum ShiftBitsToHigh(BigNum a, int shift)
{
int t = shift / 32;
int s = shift - t * 32;
ulong n, carry = 0;
BigNum result = new BigNum(a.array.Length + t + 1);
for (int i = 0; i < a.array.Length; i++)
{
n = a.array[i];
n = n << s;
result.array[i + t] = (n & 0xFFFFFFFF) | carry;
carry = (n & 0xFFFFFFFF00000000) >> 32;
}
result.array[a.array.Length + t] = carry;
return(result);
}
public BigNum Addition(BigNum a, BigNum b)
{
var maxlen = Math.Max(a.array.Length, b.array.Length);
Control(a, b, maxlen);
carry = 0;
var result = new BigNum(maxlen + 1);
for (int i = 0; i < maxlen; i++)
{
ulong temp = a.array[i] + b.array[i] + carry;
carry = temp >> 32;
result.array[i] = temp & 0xffffffff;
}
result.array[a.array.Length] = carry;
return(result);
}
public BigNum LongPowerWindow(BigNum a, BigNum b)
{
Dictionary <char, int> HexToDecimal = new Dictionary <char, int>
{
{ '0', 0 }, { '1', 1 }, { '2', 2 }, { '3', 3 }, { '4', 4 }, { '5', 5 }, { '6', 6 }, { '7', 7 }, { '8', 8 }, { '9', 9 }, { 'A', 10 }, { 'B', 11 }, { 'C', 12 }, { 'D', 13 }, { 'E', 14 }, { 'F', 15 }
};
var Bstring = b.ToString();
var result = new BigNum("1");
if (Compare(a, Zero) == 0)
{
return(Zero);
}
if (Compare(b, Zero) == 0)
{
return(One);
}
BigNum[] DegreesOfTwo = new BigNum[16];
DegreesOfTwo[0] = new BigNum("1");
DegreesOfTwo[1] = a;
for (int k = 2; k < DegreesOfTwo.Length; k++)
{
DegreesOfTwo[k] = Multiplication(DegreesOfTwo[k - 1], a);
}
for (int i = 0; i < Bstring.Length; i++)
{
var x = Bstring[i];
result = Multiplication(result, DegreesOfTwo[HexToDecimal[Bstring[i]]]);
if (i != Bstring.Length - 1)
{
for (int j = 1; j <= 4; j++)
{
result = Multiplication(result, result);
}
}
}
return(result);
}
public BigNum Substraction(BigNum a, BigNum b)
{
if (Compare(a, b) == 0 || Compare(a, b) == -1)
{
return(Zero);
}
var maxlen = Math.Max(a.array.Length, b.array.Length);
Control(a, b, maxlen);
var result = new BigNum(maxlen);
for (int i = 0; i < maxlen; i++)
{
temp = a.array[i] - b.array[i] - borrow;
result.array[i] = temp & 0xffffffff;
borrow = (temp <= a.array[i]) ? 0ul : 1ul;
}
return(result);
}
public BigNum Multiplication(BigNum a, BigNum b)
{
var maxlen = Math.Max(a.array.Length, b.array.Length);
Control(a, b, maxlen);
var result = new BigNum(a.array.Length + b.array.Length);
for (int i = 0; i < a.array.Length; i++)
{
carry = 0;
for (int j = 0; j < b.array.Length; j++)
{
ulong temp = result.array[i + j] + a.array[j] * b.array[i] + carry;
result.array[i + j] = temp & 0xFFFFFFFF;
carry = temp >> 32;
}
result.array[i + a.array.Length] = carry;
}
result = RemoveHighZeros(result);
return(result);
}
public BigNum[] LongDiv(BigNum a, BigNum b)
{
int k = Bitlen(b);
int t = 0;
BigNum r = new BigNum(a.ToString());
BigNum q = new BigNum(1);
BigNum c = new BigNum(1);
while (Compare(r, b) >= 0)
{
t = Bitlen(r);
c = ShiftBitsToHigh(b, t - k);
if (Compare(r, c) == -1)
{
t--;
c = ShiftBitsToHigh(b, t - k);
}
r = Substraction(r, c);
q = Addition(q, ShiftBitsToHigh(One, t - k));
}
BigNum[] result = new BigNum[] { q, r };
return(result);
}
public static void Control(BigNum a, BigNum b, int maxlen)
{
Array.Resize(ref a.array, maxlen);
Array.Resize(ref b.array, maxlen);
}